How do plastic bags ,straws and plastic waste end up in our wate

Erma - How do plastic bags ,straws and plastic waste end up in our water ways and oceans??. I've researched this extensively and am confused.I have NEVER thrown a plastic anything in the ocean,but apparently I am polluting the environment by recycling.What I managed to derive from data is that those put in charge of recycling plastics are negligent in their jobs and dump it in our oceans purposely or non-purposely,the wind blows millions of tons around,China wont take our Plastic waste anymore.and" around 90 percent of single-use plastic that pollutes our oceans are from Chinese Rivers".